/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.table.catalog.stats;

import java.util.HashMap;
import java.util.Map;

/**
 * Column statistics value base class.
 */
public abstract class CatalogColumnStatisticsDataBase {
	/**
	 * number of null values.
	 */
	private final Long nullCount;

	private final Map<String, String> properties;

	public CatalogColumnStatisticsDataBase(Long nullCount) {
		this(nullCount, new HashMap<>());
	}

	public CatalogColumnStatisticsDataBase(Long nullCount, Map<String, String> properties) {
		this.nullCount = nullCount;
		this.properties = properties;
	}

	public Long getNullCount() {
		return nullCount;
	}

	public Map<String, String> getProperties() {
		return this.properties;
	}

	/**
	 * Create a deep copy of "this" instance.
	 *
	 * @return a deep copy
	 */
	public abstract CatalogColumnStatisticsDataBase copy();

}
